30
1.
Power Line Polarity – The “hot” side of the power line
must be connected to the “L1” for the control to be able to
sense flame. The control detects the reversal of “hot” and
neutral. When L1 and Neutral are switched (or L1 is not
present), the control flashes “5” on the Status LED and
locks out.
2.
Interrupted Thermostat – If the thermostat demand for
heat is removed before the flame recognition period, the
control will run the inducer for the post purge period and
de-energize all outputs.
3.
Ignition Re-Try – If flame is not established on the first
trial for ignition period, the gas valve is de-energized and
the inducer remains energized for an inter-purge period of
30 seconds. The ignitor is then re-energized and the
control initiates another trial for ignition. This sequence
repeats for up to 5 trials for ignition.
4.
Ignition Re-Cycle – Flame must not be sensed for 1
second before the control responds to a loss of flame. If
flame is established and maintained during the trial for
ignition period and then flame is lost, the gas valve is de-
energized within 2 seconds, the induced draft motor
continues to run, and the control begins timing the 45
second inter-purge delay. The indoor blower motor will be
energized and/or remain energized on heat speed for the
selected delay off time.
When the inter-purge delay is over, the ignitor is re-
energized, and the control initiates another ignitor warm
up and ignition activation period. The control will re-cycle
up to 5 flame losses (4 re-cycles) within a single call for
heat before going to lockout.
5.
Call for Continuous Fan/Cooling – When a thermostat
call for continuous fan (G) without a call for heat or
cooling, the indoor fan is energized on the COOL speed
after a .25 second delay. If a call for heat (W) occurs
during continuous fan, the blower will de-energize.
A call for fan is ignored while in lockout.
6.
Limit Switch Operation – Any time the limit switch
opens, the gas valve and ignitor will be de-energized, the
indoor blower motor will run on heat speed, and induced
draft motor will run continuously. Control status LED
flashes “1.”
When the switch re-closes, the induced draft motor will
run through post-purge and the indoor blower will run
through the selected fan off delay. The control will return
to normal operation after the blower off delay is completed.
7.
Pressure Switch – The control shall ignore pressure
switch openings of less than 1 second (the gas valve will
momentarily de-energize while the pressure switch is
open, this may cause a loss of flame). To prevent pressure
switch faults from being treated as flame losses, the
control checks to see if the pressure switch has been
open momentarily within 2 seconds prior to the flame loss.
If the pressure switch was open any time within the 2
seconds prior to a flame loss, the control assumes the
flame loss was due to the open pressure switch and
responds as described below.
If the pressure switch opens for more than 1 second after
flame has been established, the control shall de-energize
the gas valve, run through a normal 30 second post-purge
and selected heat blower off delay. When the blower off
delay is complete, the control shall start an ignition
sequence if the thermostat is still calling for heat.
If the pressure switch opens for more than one second
during a pre-purge or inter-purge, the control shall wait for
the pressure switch to close. The purge time re-starts
when the pressure switch closes. The control status LED
will flash “2.” If the pressure switch is closed when the call
for heat occurs, the control will begin to flash “3” on the
status LED after 10 seconds and wait indefinitely for the
pressure switch to open.
8.
Flame sense – Flame is normally sensed through the hot
surface ignitor using flame rectification. Open circuit
flame sense voltage should be approximately 120 VAC
line voltage. Minimum flame current required to sense
flame is 0.5 microamps DC. Normal microamps is 3 or
higher. To test, install microamp meter in series with
ground (9) pin. If flame light is on solid microamp signal is
at least 1 microamp. If flame light is blinking, flame signal
is between 0.5 and 1 microamp, indicating a weak signal.
Check for ignitor positioning and proper ground.
9.
Undesired Flame – If flame is sensed longer than 4
seconds while the gas valve is de-energized, the control
shall energize the induced draft motor and indoor blower
on heat speed. When flame is no longer sensed, the
induced draft motor will run through post-purge and the
indoor blower motor will run through the selected heat fan
off delay time. The control will do a soft lockout, but will still
respond to open limit and flame. The Status LED will flash
rapidly when lockout is due to undesired flame.
10. Lockout – The control shall not initiate a call for heat or
call for continuous fan while in lockout. A call for cooling
operates as normal. The control will still respond to an
open limit and undesired flame.
Lockout will automatically reset after 1 hour. Lockout may
be manually reset by removing power from the control for
more than 1 second or removing the thermostat call for
heat for more than 1 and less than 20 seconds (The 20
second time limit prevents electronic thermostats from
automatically resetting lockout).
11. Power Interruption – The control will not interrupt its
operational sequence from power interruptions less than
80 mS in duration. Relay outputs will momentarily de-
energize during the interruption.
